Behavioral analysis of Microphallus turgidus cercariae in relation to microhabitat of two host grass shrimp species (Palaemonetes spp.).

The behavior of Microphallus turgidus cercariae was examined and compared to microhabitat selection of the second intermediate hosts of the parasite, Palaemonetes spp. grass shrimp. Cercariae were tested for photokinetic and geotactic responses, and a behavioral ethogram was established for cercariae in control and grass shrimp-conditioned brackish water.

In Vitro Insemination of the Microphallid Digenean Gynaecotyla adunca.

In vitro cultivation of adult digeneans can benefit research on their biology and contribute to the development of new drugs and vaccines. Successful in vitro growth of excysted metacercariae into adults capable of producing embryonated eggs typically requires that the worms be inseminated. The goal of the study was to develop an in vitro insemination procedure for the progenetic microphallid digenean Gynaecotyla adunca.

Optimization of Conditions for In Vitro Culture of the Microphallid Digenean Gynaecotyla adunca.

In vitro cultivation of digeneans would aid the development of effective treatments and studies of the biology of the parasites. The goal of this study was to optimize culture conditions for the trematode, Gynaecotyla adunca. Metacercariae of the parasite from fiddler crabs, Uca pugnax, excysted in trypsin, were incubated overnight to permit fertilization, and were cultured in different conditions to find those that resulted in maximum worm longevity and egg production.

Optimization of culture conditions for in vitro fertilization and reproduction of Microphallus turgidus (Trematoda: Microphallidae).

Most attempts to culture adult digeneans in vitro are unsuccessful. Even progenetic digeneans typically fail to produce infective eggs in axenic culture. However, metacercariae of Microphallus turgidus grown in vitro mature into adults and release eggs infective to the hydrobiid snail Spurwinkia salsa.

In vitro cultivation of Microphallus turgidus (Trematoda: Microphallidae) from metacercaria to ovigerous adult with continuation of the life cycle in the laboratory.

In vitro cultivation of trematodes would aid studies on the basic biology of the parasites and the development of chemotherapies and vaccines. Our goal was to measure the in vitro survival and maturation of metacercariae of Microphallus turgidus under different culture conditions. Metacercariae of M.

Prevalence of antibodies to Trypanosoma cruzi in raccoons (Procyon lotor) from an urban area of northern Virginia.

Raccoons (Procyon lotor) are reservoir hosts for Trypanosoma cruzi. A 3-yr-long serological survey was conducted to determine the prevalence of antibodies to this zoonotic parasite in raccoons collected from Fairfax County, Virginia, a suburban/urban area outside Washington, D.C.

Effects of Microphallus turgidus (Trematoda: Microphallidae) on the predation, behavior, and swimming stamina of the grass shrimp Palaemonetes pugio.

The effect of the trematode Microphallus turgidus on its second intermediate host, the grass shrimp, Palaemonetes pugio, was tested. To do so, we measured the susceptibility of infected and uninfected shrimp to predation by the mummichog, Fundulus heteroclitus. Shrimp behavior was compared in the presence and absence of a fish predator, and the swimming stamina and backthrust escape responses of infected and uninfected shrimp were measured.

In vitro excystation of metacercariae of Microphallus turgidus under different physicochemical conditions.

This study examined the excystation of metacercarial cysts of Microphallus turgidus under varying conditions of temperature, NaCl concentration, and pH. Metacercarial cysts were dissected from abdominal muscle tissue of grass shrimp Palaemonetes pugio, and immediately incubated for 24 h under one of the following abiotic conditions: temperature (22, 26, 30, 34, 38, and 42 degrees C), NaCl concentrations (0.5, 0.

Amplification of Trypanosoma cruzi-specific DNA sequences in formalin-fixed raccoon tissues using polymerase chain reaction.

This investigation applied polymerase chain reaction (PCR) using 3 sets of Trypanosoma cruzi-specific primers to amplify DNA from 31 archived formalin-fixed and fresh-frozen raccoon hearts. PCR successfully amplified T. cruzi-specific sequences, with at least 1 primer set, from multiple sites within the myocardium of formalin-fixed and fresh-frozen raccoon hearts that had previously tested positive using enzyme-linked immunosorbent assay and indirect immunofluorescent antibody titer in the absence of positive hemoculture results.

Prevalence, geographic distribution, and fitness effects of Microphallus turgidus (trematoda: Microphallidae) in grass shrimp (Palaemonetes spp.) from coastal Georgia.

Grass shrimp, Palaemonetes pugio Holthuis and P. vilgaris (Say), were collected at 11 localities along the coast of Georgia and surveyed for digenetic trematode metacercariae. The effect of trematode infection on grass shrimp fitness was also examined.